Add infrastructure to persist scrobble tracks to database

Unused for now.

priv/repo/migrations/20250530203701_create_scrobbled_tracks.exs

@@ -0,0 +1,16 @@
+defmodule MusicLibrary.Repo.Migrations.CreateScrobbledTracks do
+  use Ecto.Migration
+
+  def change do
+    create table(:scrobbled_tracks, primary_key: false) do
+      add :scrobbled_at_uts, :integer, primary_key: true
+      add :musicbrainz_id, :string
+      add :title, :string
+      add :cover_url, :string
+      add :scrobbled_at_label, :string
+      add :artist, :map
+      add :album, :map
+      add :last_fm_data, :map
+    end
+  end
+end